Method for obtaining natural super-cloud compositions

ABSTRACT

A method of obtaining a natural super-cloud composition of citrus components, which method entails: (a) extracting with water at a temperature of about 60-100° C. at least one citrus constituent comprising peel, core, cells, frit or juice or a combination thereof, to obtain water-extracted soluble citrus solids; (b) separating the water-extracted soluble citrus solids and discarding high mesh material, to obtain a liquor consisting essentially of low sedimented pulp; (c) enzymatically treating said liquor with pectolytic enzymes; (d) inactivating natural and added enzymes in the liquor; (e) centrifuging said liquor by hot centrifugation; (f) concentrating the centrifuged liquor; and (g) subjecting the concentrated liquor to membrane separation, wherein the membrane cut-offs are 30,000-500,000 molecular weight, and obtaining a retentate containing the super-cloud composition.

This application is a 371 of PCT/1L99/00143, filed Mar. 15, 1998.

FIELD OF THE INVENTION

The present invention relates to a method for selectively obtainingtotally natural super cloud compositions of citrus components and forobtaining a cloudy dispersion of said citrus components, especiallyuseful in the beverage industry. This method comprises a uniquecombination of enzymatic treatment of water soluble extract(WSECS-polysaccharides, mainly pectins, cellulose, hemicellulose andnonsolubles such as bioflavenoids, proteins, etc.) and separationtechniques, specifically ultrafiltration using selective membranes. Themethod further comprises emulsion of said super cloud compositions withfood grade oil, resulting in a preparation with no off flavor,bitterness or after taste, good stability and high opacity. The presentinvention also relates to super cloud compositions obtained by thismethod and to beverages containing them.

BACKGROUND OF THE INVENTION

For many years, citrus and beverage industries have been using cloudyemulsions to improve the appearance and stability of citrus based drinksconsisting of less than 60 wt % orange juice. The concepts used in thisfield are based on providing an oil- in-water emulsion with weightingagents to the citrus drinks, so that the light scattering from the oildroplets will provide additional opacity to the final drink. In order tominimize creaming of the oil droplets, resulting in a ringing effect, ahigh density weight agent is added to the oil phase and droplets arereduced to a micronal range size. The thermodynamic instability of theemulsion is controlled, to some extent, with emulsifiers or stabilizers.Additives such as colorants, preservatives etc. could be added to thecontinuous water phase (water soluble additives) or to the oil phase(oil soluble additives).

The classical weighting agent, brominated vegetable oil (BVO), wasbanned in many countries due to its hazardous effects, and was replacedby ester gums (some synthetic and some extracted from plants). Also themonomeric emulsifiers used, such as Span and Tween have been replaced byvarious types of gum Acacia or gum Arabic, that when used in excess (upto 20 wt %), impart stability to the emulsion. All these cloudyemulsions require significant amounts of emulsifier to stabilize theemulsion against flocculation and coalescence.

According to the new trend, to replace synthetic components by totallynatural components, attempts were made to utilize proteins andhydrocolloids and especially pectins and use them in cloudy emulsions.Pectins are concentrated in citrus peels. Some fractions of pectins havebeen known to stabilize certain dispersions of solid particles in thejuice and to serve as an emulsifier to some of the essential oilspresent in the juice. Peel extracts and peel extract emulsions arepresently used in cloudy emulsions but their performance is poor (adilution of not more than 60, practically 30 to 50, could be made withabsorbance of 1.0 OD with these samples). In addition, these emulsionsare non-stable and impart bitterness, off flavor and some cloudinstability to the final product.

U.S. Pat. No. 5,202,142 describes a process for the production of cloudyjuices with stable cloudiness from natural products only byultrafiltrating the raw juice and mixing in filter residues of crossflow filtration. Moreover, stabilizing agents must be mixed into theproduct of this US patent, to prevent the agglomeration of the cloudyparticles.

The complex microstructure of polysaccharides—proteins—crystallineparticles in the juice and other fruit components are not fullyunderstood and it is almost impossible to extract them with out causingdamage to the internal microstructure responsible for the cloudy effect.

In light of the present state of the art, the present inventionsurprisingly provides a method for specific and selective extraction ofthe active—cloudy—colloid composition from citrus peels and other partsof the fruit, comprising a unique combination of enzymatic treatment ofwater soluble extract citrus solids (WSECS) and separation techniques.The preparation obtained by this method is an all natural cloudy activepreparation, having a selective internal and citrus derived compositionof phenolic compounds, polysaccharides and other emulsifying componentswhich, in emulsion, provide a preparation with excellent cloud, goodstability and no after taste, off flavor, ringing effect or bitterness.The cloudy active compositions according to the present invention willtherefore be referred to as “super cloud compositions”.

SUMMARY OF THE INVENTION

The present invention relates to a method for obtaining natural supercloud compositions of citrus components, for use in beverages. (In thepresent invention the word compositions refers to citrus componentseither in emulsion or not). The method comprises:

a) applying water extraction on at least one of the following; peel,core, cells, frit, juice of citrus, obtaining water extracted solublecitrus solids;

b) separating said water extracted soluble citrus solids, discardinghigh mesh matter and obtaining a liquor consisting of low sedimentedpulp;

c) applying enzymatic treatment on said liquor by pectolytic enzymes;

d) inactivating natural and added enzymes in the liquor;

e) centrifuging said liquor (hot centrifugation) obtaining a stable highcloud—low concentration of sedimented pulp;

f) further concentrating the liquor;

g) applying membrane separation technologies on said concentratedliquor, obtaining a retentant containing the required super cloudcompositions;

The obtained super cloud compositions may be further emulsified with oilsuch as vegetable oils, Tall oils, marine oils, tropical oils,terpenless, essential citrus oils and essential vegetable or spicesoils, and the oil concentration in the emulsion may be up to 15 wt %.The emulsion is homogenized to obtain particles of less than average 10μm, preferably less than 1 μm. Water soluble or oil soluble coloringagents, or their combination, may be further added to the emulsion.Finally, the received cloudy emulsion may be added to a beverageachieving a cloudy effect.

The present invention relates to cloudy active compositions obtained bythe said method and to beverages prepared according to this method.

Detailed Description of the Invention

The present invention relates to a method for selectively obtainingcloudy active compositions of citrus components (refered to in thepresent invention as “totally natural super cloud compositions” or“super cloud compositions”) and for obtaining a cloudy dispersion ofsaid citrus components. This method uses one or several of theprocessing streams of the juice and fruit industry, known also as watersoluble extract citrus solids (WSECS), which consists of variouscompositions of core, cells, peel, frit and juice. A typical compositionconsists of 55-65% (solids) peel, 20-30 wt % core materials and 15-20%frit.

In the method of the present invention WESCS compositions are extractedwith hot aqueous solutions, and/or deionized and/or condensated water orby heating a mixture of water and citrus compositions, for a period of20-60 minutes, preferably 20-40 minute, at 30-100° C., or best at 55-60°C. Preferably, the water extraction is applied to any combination ofcitrus components which comprise up to about 70 wt % of the citrus fruitor to citrus components enriched with frits.

The extracted material is further decanted and/or separated (by press,finishers or decanters) removing the high mesh matter (20-40 mesh), andthe lower sedimented pulp. The supernatant (known as liquor) in whichthe pulp level is controlled at up to 15 wt %, preferably at 1-5wt %, issubject to enzymatic treatment applied at 3-4 Brix, and, depending onthe enzymes used, at levels of 5-100 ppm, preferably 5-20 ppm, at 30-55°C., for 20-60 minutes. The enzymatic process is controlled to adjust theviscosity, gelling properties, cloud stability and colloid stability tothe required characteristics of the product. Pectolytic enzymes, such asCitrozyme cloudy 100 (NOVO) and pectinex 3XL (NOVO), are used to cleavethe pectolytic matter and to obtain low molecular weight pectins, whichare soluble and surface active. The enzymes are selected according tothe feed characteristics of the fruit components, as per season,maturity, species, citrus hybrids and geographical location.Compositions of peel, core, cells, frit, juice of citrus fruits may varyfrom region to region and within species and, as a result, theconditions of the method of the present invention, may vary.

The enzymatic reaction is terminated by pasteuration at 95-105° C. forup to 90 seconds. Pasteuration results also in the inactivation of thenatural enzymes and stops any enzymatic and microbial activity in thetreated system. The pasteurized slurry (liquor) is treated by hotcentrifugation (juice desludger, usually known in the art to be in thetemperature range of 70-105° C.), for best control of the cloudinstability factor or components, such as oxalic pectins (salts),coagulated particles etc. The product is at 3-5 Brix and is frutherpre-evaporated to 6-12 Brix, preferably 7-8 Brix.

The concentrated product is subjected to separation techniquesconsisting of microfiltration or, preferably, ultrafiltration.(Ultrafiltration relates to the use of membrane cutt—off of about 5000to 500,000 molecular weight and microfiltration relates to membrane cutoffs of molecular weights higher than 500,000 molecular weight). Amembrane system batch type (one stage) may be used or a continuoussystem (multistage). Preferably, the ultrafiltration is by using amultistage configuration system, by utilizing a hollow fiber system of60-106 mil at 40-60° C. wherein the membrane cut—offs are 5000-500,000molecular weight at a flow rate of 40−3 liter/hour/ m² of the permeate.The product is further concentrated, preferably by evaporation (or byadditional membranes), to 10-30 Brix. The ultrafiltration, carried outin a balanced way, utilizing specifically sized membranes, results in aconcentrated retentant (known also as concentrate) containing the cloudyactive compositions (refered to in the present invention as super cluodcompositions). The clear permeate, is removed. This permeate consists ofmost of the low molecular weight oligomeric sugars, low MW pectinates,some proteins (mainly peptides) and undesirable polyphenols(destabilzing the emulsions). In this process some of the free andoligomeric sugars and the bitter components are removed and avoided fromthe final product. The retentant contains some residues such ashydrocolloids, proteins, sugars and other phenolic components such assimple phenols, polyphenols and bioflavonodes (esterified by glycosidesand non—esterified compositions), but mainly insoluble polyphenols andbioflavanoids, in a solid crystalline form, such as naringine fromgrapefruits or hesperidine from oranges. In addition, the retentantcontains the surface active pectins obtained in the enzymatic process.These compounds may further be emulsified with any food grade oil, suchas vegetable oils, Tall oils, marine oils, tropical oils, terpenless,essential citrus oils and essential vegetable or spices oils etc. Theoil concentration in this emulsion may vary from 1 to 15 wt %,preferably 3-10 wt %. The emulsion/dispersion may further be homogenizedto obtain droplets/particles of less than average 10 μm, preferably lessthan 1 μm, which are added to any beverage to achieve a cloudy effect.

The obtained emulsion/dispersion is compatible with any water solubleand/or oil soluble coloring agents such as carmine, lycopene,β-carotene, Lutein, xantophils, etc.

This method provides a unique mixture of two different populations oflight scattering particles, namely soluble oil droplets coated bysurface active pectin polymers and insoluble polyphenols andbioflavonoids broken down to the required sized particles and protectedby the active emulsifying agents. This is an improved composition ofcitrus components, with good emulsifying properties (on oil droplets)and good stabilization activity (on the solid crystalline matter). Thiscombination provides accumulated light scattering, achieving an improvedcloudy effect. The emulsion obtained by the method of the presentinvention does not include bitter components and is a superior system ofliquid—liquid emulsion and solid—liquid dispersion for the production ofcloudy beverages with stable cloudiness with no off flavor, bitternessor after taste.

The super cloud obtained in the method of the present invention may beof a concentration of 20-30 Brix, viscosity of 100-5000 cps, may containwater soluble pectins in a concentration of 5,000-20,000 mg/liter(10-11.2 Brix) and in a dilution of 1:25 may have a cloud index at 560nm of 20-0% T. The present invention further relates to cloudy activecompositions, especially soluble surface active low molecular weightpectins and proteins and insoluble polyphenols and bioflavonoids,obtained by the method of the invention and to beverages containingthese compositions.

The said invention will be further illustrated by the followingexamples. These examples do not intend to limit the scope of theinvention but to demonstrate and clarify it only.

EXAMPLE NO. 1

1. A mixture of 50 wt % peel, core, frit and juice residue taken fromwhite grapefruit (Marsh seedless) was crushed by a hummer crusher whileblending with water at 85° C. in a ratio of 1:1.5 (fruit components:water).

2. The high mesh (pumass) was separated by decantors yielding a juice of3.6° Brix and 10% pulp content.

3. The juice was subject to treatment by pectolitic enzymes (Pectinex3XL, Novo), 10 ppm (weight/weight) for 24 minutes.

4. Pasteurization at 98° C. for 60 seconds.

5. Centrifugation at a rate of 5000 Liter/hr for removal of finesedimented pulp. This step resulted in product at 3.60 Brix with 0.5%sedimented pulp

6. Concentration to 7 Brix.

7. Feeding to a 2 stage continuous membranal system.

Membrane type: H.F-PM-10/60 mil. Working temperature 50° C.

Concentration Factor (CF)=9, ie: the membranal concentration ratio ofpermeate:retentent=9: 1. The resulting retentent Brix was 9.1

8. Concentration by vacuum with a batch cocentrator to 26.1 Brix and SO₂preservation at 2500 ppm.

9. The obtained super-cloud was tested and confirmed as stable and highcloudy material. (See results in table 1.)

EXAMPLE NO. 2

Same as example no. 1 with the following changes:

1. The emzymatic treatment was carried out at 12 ppm.

2. The membranal concentration was CF=10. The resulting retentant Brixwas 9.45

3. The vacuum concentration by the batch concentrator was to 28.2 Brix.(See results in table 1.)

EXAMPLE NO. 3

1. A mixture of peel, core, frit and juice residue which comprised 57%wt of the fruit, taken from Shamuti oranges was crushed by a hummercrusher while blending with water at 82° C./ in a ratio of 1:2 (fruitcomponents: water).

2. The rough solid particles were separated by decantors yielding ajuice of 3.9° Brix and 11% pulp content.

3. The juice was subject to treatment by pectolitic enzymes (Pectinex3XL, Novo), 13 ppm (weight/weight) for 20 minutes.

4. Pasteurization at 102° C. for 60 seconds.

5. Centrifugation at a rate of 5000 Liter/hr (83 liter/hour/m²)forremoval of light suspensions.

This step resulted in product at Brix3.9 with 0.8% sedimented pulp

6. Concentration to 8-9 Brix.

7. Feeding to membranal system- 2 stages in continuous process.

Membrane type: H.F-PM-10/60 mil. Working temperature 50° C.

Concentration Factor (CF)=9. The resulting retentent Brix was 12.0

8. Concentration by vacuum with batch cocentrator to 25.9 Brix and SO₂preservation at 2500 ppm

9. The obtained super-cloud was tested and confirmed as stable and highcloudy material. (See results in table 2.)

EXAMPLE NO. 4

Same as example no.3 with the following changes:

1. The extract liquor was at 3.6 Brix and 8% pulp.

2.10 ppm enzymatic treatment.

3. CF of the membranal system was 10.2 The charged product was at 7.0Brix

4. The retentent Brix was 9.5-10

5. Final concentration was 25.1 Brix. (See results in table 2.)

EXAMPLE NO. 5

Same as example 3 with the following changes:

1. The water: fruit ratio was 2.5:1.

2. The extract liquor was at 3.0 Brix and 6% pulp.

3.17 ppm enzymatic treatment.

4. CF of the membranal system was 10.0, The charged product was at 8-9Brix

5. The retentent Brix was 11.8

6. Final concentration was 25.7 Brix.

7. The product was packed in sterile aseptic packages. (See results intable 2.)

EXAMPLE NO. 6

Same as the previous example with the following changes:

1. The water: fruit ratio was 2.25:1.

2. The extract liquor was at 3.5 Brix and 9-10% pulp.

3.17 ppm enzymatic treatment.

4. The retentent Brix was 12.0

5. Final concentration was to 28.8 Brix.

6. The product was packed in sterile aseptic packages. (See results intable 2.)

EXAMPLE NO. 7

Same as the previous example with the following changes:

1. The water: fruit ratio was 2:1.

2. The extract liquor was at 3.9 Brix and 10-12% pulp.

3. Final concentration was to 23.4 Brix. (See results in table 2.)

EXAMPLE NO. 8,9,10

In all these examples Valencia oranges were used as citrus source. Themain processing parameters and results are listed in table 2.

Preparation of Cloudy Emulsions Based on the Super Cloud EXAMPLE NO. 11

The super-cloud from example 1 was blended with 6% vegetable oil andwith 15% water. The obtained emulsion was homogenized in a double stagepiston homogenizer at 250 Atm. The final emulsion gave a high and stablecloud. The Optical Density (OD), measured at 580nm in a dilution of 1:25in a 11.2 Brix syrup was 0.98. Repeated measurements of the same dilutedproduct after 1 and 4 weeks gave OD values of 0.92 and 0.89respectively, indicating a very stable cloud. No ring was observed after4 weeks.

EXAMPLE NO. 12

The super-cloud from example 1 was blended with 10% orange oil and with15% water. The obtained emulsion was homogenized in a double stagepiston homogenizer at 280 Atm. The final emulsion gave a high and stablecloud. The Optical Density (OD), measured at 580 nm in a dilution of1:25 in a 11.2 Brix syrup was 1.08. Repeated measuremnts of the samediluted product after 1 and 4 weeks gave OD values of 0.94 and 0.69respectively, indicating a non stable cloud. A ring was observed after 3weeks.

EXAMPLE NO. 13

The super-cloud from example 6 was blended with 6% vegetable oil andwith 10% water. The obtained emulsion was homogenized in a double stagepiston homogenizer at 250 Atm. The final emulsion gave a high and stablecloud. The obtained average droplet size was 1.3 μ. The Optical Density(OD), measured at 580 nm in a dilution of 1:25 in 11.2 Brix syrup was1.04 . Repeated measuremnts of the same diluted product after 1 and 4weeks gave OD values of 0.99 and 0.94 respectively, indicating a verystable cloud. No ring was observed after 4 weeks.

TABLE 1 Supercloud concentrate from Grapefruit Brix of 24 hr ExamProcess Super- Brookfield W. Soluble Cloud Index Imhoff No. ConditlonsCloud Viscosity Bostvic Pectins (1:25,560 nm) (conus) 1 7 Brix, 26.12120 cps 17 cm 15,200 mg/l 13.7% T 0.3% 10 ppm Enz. Treat. UF-C.F = 9 27 Brix, 28.2 3640 cps 14 cm 13,900 mg/l 20.9% T 0.2% 12 ppm Enz. Treat.UF-C.F = 10

TABLE 2 Supercloud concentrate from Orange Brix of 14 days 24 hr ExamProcess Super- Brookfield Cloud Index column Imhoff No. Conditlons CloudViscosity Bostvic (1:25,560 nm) 100 ml (conus) 3 8-9 Brix, 25.9 1060 cps19 cm 2.9% T 87% 0.14% Shamuti 0.8% acid 13 ppm Enz. Treat. UF-C. F=9 47 Brix, 25.1 2200 cps 15 cm 1.7% T 93% 0.1% Shamuti 1.0% acid 10 ppmEnz. Treat. UF-C.F = 10.2 5 8.5 Brix, 25.7 1240 cps 15 cm 0.8% T 95%0.2% Shamuti 0.7% acid 17 ppm Enz. Treat. UF-C.F = 10 6 8.5 Brix, 28.81300 cps 14 cm 1.0% T 90% 0.12% Shamuti 0.8% acid 17 ppm Enz. Treat.UF-C.F = 10 7 8.5 Brix, 23.4 1510 cps 17 cm 0.9% T 95% 0.1% Shamuti 0.7%acid 17 ppm Enz. Treat. UF-C.F = 10 8 8 Brix, 27.6 1850 cps 17 cm 1.0% T88% 0.1% Valencia 0.6% acid 20 ppm Enz. Treat. UF-C.F = 8 9 8 Brix, 27.82030 cps 15 cm 1.3% T 87% 0.1% Valencia 0.6% acid 16 ppm Enz. Treat.UF-C.F = 8 10  8 Brix, 21.7 4000 cps 13 cm 1.5% T 100%  0.12% Valencia0.7% acid 12 ppm Enz. Treat. UF-C.F = 8

What is claimed is:
 1. A method for obtaining a natural super cloudcomposition of citrus components comprising the steps of: a) extractingwith water at a temperature of about 60° C.-100° C. at least one citrusconstituent comprising peel, core, cells, frit or juice or a combinationthereof, for 20-60 minutes under continuous stirring, to obtainwater-extracted soluble citrus solids; b) separating saidwater-extracted soluble citrus solids, and discarding high mesh matter,to obtain a liquor consisting essentially of low sedimented pulp havinga positive concentration of up to about 15wt % solids; c) enzymaticallytreating said liquor with a cocktail of pectolytic enzymes at 30-55° C.for at least 20 minutes, wherein said cocktail of enzymes comprises oneor more pectolytic enzymes capable of producing soluble and surfaceactive pectins from said liquor; d) inactivating natural and addedenzymes in the liquor; e) centrifuging said liquor by hot centrifugationin a juice desludger; f) concentrating the centrifuged liquor to obtaina concentration of from 6 to 12 Brix; and g) subjecting saidconcentrated liquor to membrane separation by utilizing a hollow fibersystem of about 60-106 mil at about 40-60 ° C. at a permeate flow rateabout 3-40 liter/hour/m², wherein the membrane cut-offs are30,000-500,000 molecular weight, and obtaining a retentate containingthe super cloud composition.
 2. The method of claim 1, which furthercomprises after step g), the step of concentrating the retentate from 10to 30 Brix.
 3. The method of claim 1, which further comprises after stepg), the step of emulsifying the obtained super cloud composition withoil and homogenizing the composition, thereby obtaining particles ofless than an average of 10 μm.
 4. The method of claim 1, which furthercomprises after step g), the step of adding the super-cloud compositionto a beverage to produce cloudiness in said beverage.
 5. The method ofclaim 1, wherein the step of water extraction a) is applied to said atleast one citrus constituent which comprises up to about 70 wt % of thecitrus fruit.
 6. The method of claim 1, wherein the step of waterextraction a) is applied to said at least one citrus constituentcontaining frit.
 7. The method of claim 1, wherein inactivation of theenzymes in step d) is effected by pasteurizing at 90-105 ° C. for up to90 seconds.
 8. The method of claim 1, wherein said membrane separationg) is effected with a batch membrane system or a continuous system. 9.The method of claim 3, wherein the oil for emulsifying the obtainedretentate is food grade oil.
 10. The method of claim 9, wherein the foodgrade oil is selected from the group consisting of vegetable oils, Talloils, marine oils, tropical oils, terpenless essential citrus oils,essential vegetable and spice oils.
 11. The method of claim 3, whereinthe step of emulsifying the obtained super cloud composition with oiland homogenizing is effected with an oil concentration in the emulsionof from a positive amount to up to 15 wt %.
 12. The method of claim 3,wherein water-soluble or oil-soluble coloring agents, or theircombination are further added to the emulsion.
 13. The method of claim12, wherein the coloring agents are selected from carmine, lycopene,β-carotene, lutein and xantophils.
 14. The method of claim 1, whereinthe retentate of step g) comprises hydrocolloids, proteins, sugars,phenols, polyphenols or bioflavonoids or a mixture thereof.
 15. Themethod of claim 14, wherein the retentate of step g) comprisespolyphenols and bioflavonoids.
 16. The method of claim 15, wherein theretentate of step g) comprises narirutin or hesperidin.
 17. The methodof claim 11, wherein the oil concentration is from 3 to 10 wt %.
 18. Themethod of claim 1, wherein said one or more pectolytic enzymes comprisesCitrozyme cloudy 100 or Pectinex 3XL or both.
 19. The method of claim 1,wherein said step e) is effected such that the hot centrifugation isconducted at a temperature of 70-105° C., to produce a product of from 3to 5 Brix.
 20. The method of claim 1, wherein said at least one citrusconstituent is obtained from oranges.
 21. The method of claim 1, whereinsaid at least one citrus constituent is obtained from grapefruit.
 22. Asuper cloud composition produced by the method of claim
 1. 23. The supercloud composition of claim 22, which comprises a concentration of from20-30 Brix, viscosity of from 100-500 cps, and water soluble pectins ina concentration of from 10,000-20,000 mg/liter and at a dilution of 1:25has a cloud index at 560 nm of 0-20%T.
 24. A beverage produced by themethod of claim 4.